What is 802.1Q trunk port?
Table of Contents
What is 802.1Q trunk port?
An 802.1Q trunk link provides VLAN identification by adding a 4-byte tag to an Ethernet Frame as it leaves a trunk port. Because the frame has been changed, a new frame check sequence (FCS) must also be computed and added to the frame.
What is dot1q tunneling ethertype?
802.1Q tunneling enables service providers to use a single VLAN to support customers who have multiple VLANs, while preserving customer VLAN IDs and keeping traffic in different customer VLANs segregated. A port configured to support 802.1Q tunneling is called a tunnel port.
What does Switchport trunk encapsulation dot1q do?
switchport trunk encapsulation dot1q sets the encapsulation mode of the trunk interface to the industry standard 802.1Q. switchport trunk encapsulation isl sets the encapsulation mode of the trunk interface to proprietary ISL.
How do you use encapsulation dot1q?
Configuring ROAS
- Use the interface type number.
- Use the encapsulation dot1q vlan_id command in subinterface configuration mode to enable 802.1Q and associate one specific VLAN with the subinterface.
- Use the ip address address mask command in subinterface configuration mode to configure IP settings (address and mask).
How do I enable Dot1Q encapsulation?
How do I enable DOT1Q encapsulation?
What is DOT1Q protocol?
IEEE 802.1Q, often referred to as Dot1q, is the networking standard that supports virtual local area networking (VLANs) on an IEEE 802.3 Ethernet network. The standard defines a system of VLAN tagging for Ethernet frames and the accompanying procedures to be used by bridges and switches in handling such frames.
What is encapsulation Dot1Q command?
One command (encapsulation) enables trunking and defines the VLAN whose frames are considered to be coming in and out of the subinterface. The ip address command works the same way it does on any other interface.
What is Switchport mode trunk?
switchport mode trunk: Puts the interface into permanent trunking mode and negotiates to convert the neighboring link into a trunk link. The interface becomes a trunk interface even if the neighboring interface is not a trunk interface.
What is Dot1Q protocol?
What is DOT1Q tunneling?
802.1Q tunneling enables Service Providers to use a single VLAN to support customers who have multiple VLANs, while preserving customer VLAN IDs and keeping traffic in different customer VLANs segregated. A port configured to support 802.1Q tunneling is called a tunnel port.
Does Switchport mode trunk allow all VLANs?
The all option in the switchport trunk allowed vlan command means all VLANs, so you can use it to reset the switch to its original default setting (permitting all VLANs on the trunk).
What does Switchport trunk allowed do?
The switchport trunk allowed vlan command is used to specify the list of VLANs that are allowed on a trunk port. When a Layer 2 interface on a Cisco IOS device is configured to operate in trunk mode, the default setting is for the interface to carry all of the VLANs defined on the switch.
